Fix progress_printer using wrong variable in on_test_batch_end (#15064)

The on_test_batch_end() method was incorrectly referencing
self.total_validation_steps instead of self.total_test_steps,
causing an AttributeError when running trainer.test() since
total_validation_steps may not be initialized during testing.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: yurekami

nemo/lightning/pytorch/callbacks/progress_printer.py

@@ -218,7 +218,7 @@ def on_test_batch_end(
             return
         n = int((batch_idx + 1) / get_num_microbatches())
         if self.should_log(n):
-            print(self.test_description + f": iteration {n}/{self.total_validation_steps}")
+            print(self.test_description + f": iteration {n}/{self.total_test_steps}")
 
     def should_log(self, n):
         return n % self.log_interval == 0